Darpa: Now We Know Why Our Mach-20 Ship Crashed

It took six months, but the Defense Advanced Research Projects Agency finally has a handle on what caused its hypersonic weapon prototype to “terminate” itself over the Pacific Ocean back in April. The findings have paved the way for a fresh round of tests for the Mach-20 flier, potentially leading to a new class of superfast weapons.

The Hypersonic Test Vehicle 2 — a 12-foot, 2,000-pound wedge packing a three-stage Minotaur booster — launched without incident from California on April 22. It climbed to the edge of space for a planned 30-minute, 4,000-mile jaunt toward Kwajalein in the middle of the Pacific.

In other words, the HTV wobbled too much. Rather than risking an out-of-control flight, the bot self-destructed. On the bright side, according to a chipper Darpa release, the failed test “demonstrated successfully the first-ever use of an autonomous flight-termination system.”

Lockheed built two HTV-2 test vehicles, but Darpa held off on further flights until engineers could say for sure what killed the first HTV. Now the agency is ready to try again, with a few tweaks. “Engineers will adjust the vehicle’s center of gravity, decrease the angle of attack flown, and use the on-board reaction-control system to augment the vehicle flaps when HTV-2 flies next summer.”

Time was, Pentagon planners anticipated adapting HTV into a weapon capable of striking any target in the world within minutes of launch from a base in the United States. With that ambition running afoul of (very sensible) diplomatic concerns, planners instead envisioned using hypersonic technology in a new, superfast bomber.

Now it’s clear the Pentagon wants a less-ambitious bomber similar to models already in service. So instead, HTV-2 and its ilk are likely to lead to a new generation of missiles that can be carried by today’s manned planes.

But first, HTV needs to fly a full test circuit without wobbling — and self-terminating.